Commit 29132d16 authored Jan 20, 2026 by Arnaldo Carvalho de Melo

perf list: Don't write to const memory



Something now detected on fedora 44, where strchr() returns const if it
is passed a const pointer:

  util/print-events.c: In function 'print_sdt_events':
  util/print-events.c:89:29: error: initialization discards 'const' qualifier from pointer target type [-Werror=discarded-qualifiers]
     89 |                 char *bid = strchr(sdt_name->s, '@');
        |                             ^~~~~~

Fix it by using strchrnul() + strncmp() instead of temporarily scrubbing
it with '\0'.

Reviewed-by: Ian Rogers <irogers@google.com>
Suggested-by: David Laight <david.laight.linux@gmail.com>
Link: https://lore.kernel.org/r/20260121112536.27fd5d11@pumpkin


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

parent 9a0a5b5a

tools/perf/util/print-events.c

+3 −8

Original line number	Diff line number	Diff line
		@@ -97,14 +97,9 @@ void print_sdt_events(const struct print_callbacks print_cb, void print_state)
		} else {
		next_sdt_name = strlist__next(sdt_name);
		if (next_sdt_name) {
		char *bid2 = strchr(next_sdt_name->s, '@');
		const char *bid2 = strchrnul(next_sdt_name->s, '@');

		if (bid2)
		*bid2 = '\0';
		if (strcmp(sdt_name->s, next_sdt_name->s) == 0)
		show_detail = true;
		if (bid2)
		*bid2 = '@';
		show_detail = strncmp(sdt_name->s, next_sdt_name->s, bid2 - next_sdt_name->s) == 0;
		}
		}
		last_sdt_name = sdt_name->s;